Consolidate Linux openat implementation

This patch consolidates the open Linux syscall implementation on
sysdeps/unix/sysv/linux/open{64}.c.  The changes are:

  1. Remove wordsize-64 openat{64}.
  2. For architetures that define __OFF_T_MATCHES_OFF64_T openat64
     will be default one with alias to required symbols.  Otherwise
     openat64 will pass the required O_LARGEFILE flag on syscall.

Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, and powerpc64le-linux-gnu.

	* sysdeps/unix/sysv/linux/openat.c (__libc_openat): Build only
	for !__OFF_T_MATCHES_OFF64_T.
	* sysdeps/unix/sysv/linux/openat64.c (__libc_openat64): New
	implementation based on open64.
	* sysdeps/unix/sysv/linux/wordsize-64/openat.c: Remove file.
	* sysdeps/unix/sysv/linux/wordsize-64/openat64.c: Likewise.

1 files changed, 54 insertions, 3 deletions

diff --git a/sysdeps/unix/sysv/linux/openat64.c b/sysdeps/unix/sysv/linux/openat64.c
index 9e7a2b3737..4942061671 100644
--- a/sysdeps/unix/sysv/linux/openat64.c
+++ b/sysdeps/unix/sysv/linux/openat64.c
@@ -1,4 +1,55 @@
-#define OPENAT openat64
-#define MORE_OFLAGS O_LARGEFILE
+/* Copyright (C) 2007-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
 
-#include "openat.c"
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fcntl.h>
+#include <stdarg.h>
+
+#include <sysdep-cancel.h>
+
+/* Open FILE with access OFLAG.  Interpret relative paths relative to
+   the directory associated with FD.  If OFLAG includes O_CREAT or
+   O_TMPFILE, a fourth argument is the file protection.  */
+int
+__libc_openat64 (int fd, const char *file, int oflag, ...)
+{
+  mode_t mode = 0;
+  if (__OPEN_NEEDS_MODE (oflag))
+    {
+      va_list arg;
+      va_start (arg, oflag);
+      mode = va_arg (arg, mode_t);
+      va_end (arg);
+    }
+
+#ifdef __OFF_T_MATCHES_OFF64_T
+# define EXTRA_OPEN_FLAGS 0
+#else
+# define EXTRA_OPEN_FLAGS O_LARGEFILE
+#endif
+
+  return SYSCALL_CANCEL (openat, fd, file, oflag | EXTRA_OPEN_FLAGS, mode);
+}
+
+strong_alias (__libc_openat64, __openat64)
+libc_hidden_weak (__openat64)
+weak_alias (__libc_openat64, openat64)
+
+#ifdef __OFF_T_MATCHES_OFF64_T
+strong_alias (__libc_openat64, __openat)
+libc_hidden_weak (__openat)
+weak_alias (__libc_openat64, openat)
+#endif